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000
FXUS61 KCTP 070922
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
422 AM EST FRI MAR 7 2014

.SYNOPSIS...
A RIDGE OF HIGH PRESSURE AND LARGE WEDGE OF DRY AIR WILL EXTEND FROM
THE NEW ENGLAND STATES SOUTHWEST ACROSS PENNSYLVANIA TODAY AND
TONIGHT...WHILE LOW PRESSURE OVER THE CAROLINAS SLIDES HARMLESSLY
OUT TO SEA. A WEAK...AND MAINLY DRY COLD FRONT WILL SLIDE SOUTHEAST
FROM THE GREAT LAKES AND CROSS PENNSYLVANIA SATURDAY AFTERNOON AND
EVENING. A DRY AND SEASONABLY COLD NORTHWEST FLOW WILL FOLLOW FOR
SUNDAY AND MONDAY. THE WEATHER PATTERN APPEARS TO BECOME QUITE
ACTIVE WEDNESDAY INTO THURSDAY AS NORTHERN AND SOUTHERN BRANCHES OF
THE JET STREAM LINK UP TO PRODUCE A COMPLEX STORM SYSTEM THAT COULD
IMPACT MUCH OF THE REGION EAST OF THE MISSISSIPPI VALLEY.

&&

.NEAR TERM /UNTIL 8 AM THIS MORNING/...
DEEP SOUTHERN STREAM WAVE AND STRONGLY BACKING MID AND UPPER LEVEL
FLOW ACROSS THE CAROLINAS AND SOUTHERN MID ATLANTIC REGION WILL
SPREAD A THICKENING SHIELD OF MID AND HIGH CLOUDS INTO CENTRAL PENN
EARLY TODAY...WHILE A PERSISTENT SOUTHEASTERLY FLOW IN THE 925-850
MB LAYER OFF THE DELMARVA AND SRN NEW JERSEY COASTS WILL PUSH AN
AREA OF STRATUS AND STRATO CU ACROSS THE SOUTHERN THIRD TO HALF OF
THE FCST AREA THIS MORNING.


TEMPS EARLY TODAY WILL FALL A FEW MORE DEG F ACROSS THE SOUTH AND UP
TO SEVERAL DEG F OVER NORTHERN PARTS OF THE STATE /WHERE SFC
DEWPOINTS ARE 5-10F COOLER AND CLOUD COVER WILL BE RELATIVELY THIN/.

MINS AT DAYBREAK WILL VARY FROM THE UPPER SINGLE DIGITS TO LOWER
TEENS OVER THE NORTHERN MTNS...TO THE MID TEENS TO LOWER 20S
ELSEWHERE.

DURING THE EARLY TO MID MORNING HOURS...THERE`S JUST A
SLIGHT CHC FOR SOME SNIZZLE OR PATCHY -FZDZ INVOF THE LAUREL
HIGHLANDS THANKS TO THE GREATEST OROGRAPHIC COMPONENT OF THE MOIST
SERLY UPSLOPE FLOW.

&&

.SHORT TERM /8 AM THIS MORNING THROUGH 6 PM SATURDAY/...
SFC HIGH RIDGING ACROSS THE STATE FROM NE TO SW WILL BE IN CONTROL
OF OUR LOCAL WEATHER TODAY.

EXPECT LITTLE CHANGE IN THE MILKY-LOOKING...THICK ALTOSTRATUS AND
CIRROSTRATUS LAYER NEAR AND TO THE NORTH OF INTERSTATE 80. ACROSS
THE SOUTH /AND THROUGHOUT THE LOWER AND PORTIONS OF THE MID SUSQ
VALLEY/ THE INCREASING STRATUS AND STRATO CU SHOULD PRODUCE NOTHING
MORE THAN SOME PATCHY SNIZZLE OF FREEZING DRIZZLE IN AREAS WHERE THE
BEST LLVL OROGRAPHIC LIFT OCCURS VIA THE MOST SERLY LLVL FLOW.

GFS LAMP GUIDANCE INDICATES THAT MOST LOCATIONS THROUGHOUT CENTRAL
AND SOUTHERN PA WILL SEE AFTERNOON HIGHS IN THE 30-35F RANGE /THANKS
TO THE THICKER...LAYERED CLOUD COVER/...WHILE THE TYPICALLY COOLER
HIGHER TERRAIN OF THE NORTH AND WEST WILL EXPERIENCE TEMPS IN THE
MID TO UPPER 30S.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
AN ACTIVE SPLIT FLOW JET STREAM PATTERN IS FORECAST TO DOMINATE
NORTH AMERICA DURING THE LONG TERM PERIOD. A FAST MOVING NRN STREAM
JET WILL SEND SEVERAL COLD FRONTS AND REINFORCING SHOTS OF COLD AIR
INTO THE NORTHEAST DURING THE PERIOD. THE ACTIVE SRN STREAM HOWEVER
WILL LIMIT THE MOISTURE AVAILABLE FOR THE FAIRLY FLAT...NRN STREAM
SHORTWAVES AND WEAK SFC COLD FRONTAL BOUNDARIES. MOST OF THE PERIOD
LOOKS TO BE COLD AND DRY...WITH JUST A FEW BRIEF PERIODS OF LIGHT
SNOW OR FLURRIES POSSIBLE ACROSS THE NORTH AND WEST.

THE FIRST NRN STREAM COLD FRONT WILL CROSS PA ON SAT AND POSSIBLY
STALL OVER THE DELMARVA ON SUNDAY. THE SECOND FRONT APPROACHES LATE
ON TUESDAY.

THE FIRST SRN STEAM WAVE...NOW PRODUCING WINTRY WEATHER OVER
TEXAS...WILL LIFT TO THE CAROLINA COAST FRIDAY. THIS SYSTEM SHOULD
NOT MOVE FAR ENOUGH NORTH TO IMPACT WEATHER OVER PA. A SECOND
PRONOUNCED WAVE IN THE SRN STREAM WILL MOVE ACROSS THE SRN PLAINS
EARLY NEXT WEEK. INDICATIONS CONTINUE TO SUGGEST THE POTENTIAL FOR
CYCLOGENESIS OVER THE SRN APPALACHIANS NEXT TUESDAY INTO
WEDNESDAY...WITH SOME MEDIUM RANGE GUIDANCE SHOWING SIGNIFICANT
SNOWFALL NWD INTO CENTRAL PA. HAVE INCLUDED WIDESPREAD HIER CHANCE
POPS AT THIS POINT WITH SOME INCREASED LEVEL OF CONFIDENCE...BUT
STILL GIVEN THE OBVIOUS LEVEL UNCERTAINTY AT THIS TIME FRAME.

&&

.AVIATION /10Z FRIDAY THROUGH TUESDAY/...
09Z TAFS SENT.

LOWER CLDS NOW INTO THE AREA...AS FAR NORTH AS UNV.

EARLIER DISCUSSION BELOW.

A RIDGE OF HIGH PRESSURE WILL REMAIN OVER PENNSYLVANIA
TODAY...RESULTING IN A HIGH CONFIDENCE OF DRY WEATHER AND LIGHT
WINDS. THE MAIN AVIATION CONCERN WILL BE THE POSSIBILITY OF SOME
LOWER CIGS WORKING INTO SOUTHERN PA...THE RESULT OF AN
INCREASINGLY MOIST SERLY FLOW. THE AIR MASS OVER CENTRAL PA IS
INITIALLY VERY DRY...SO THERE IS NO EXPECTATION OF ANYTHING BUT
VFR CONDS THRU 06Z. HOWEVER...MDL DATA INDICATES THERE WILL BE
ENOUGH MOISTENING OF THE SFC-1KM LAYER FOR THE POSSIBILITY OF MVFR
CIGS DEVELOPING ACROSS SOUTHERN PA BY ARND DAWN. BASED ON LATEST
MDL OUTPUT...CONFIDENCE OF MVFR CIGS ACROSS SOUTHERN PA IS ABOUT
50 PCT.

ANY STRATOCU THAT DOES WORK INTO SOUTHERN PA COULD POTENTIALLY
LAST FOR A GOOD PORTION OF THE DAY...DUE TO LACK OF MIXING UNDER
SFC RIDGE AND VEIL OF HIGH CLOUDS.

OUTLOOK...
SAT...EARLY AM FOG POSSIBLE. EVENING LOW CIGS POSS W MTNS.
SUN-TUE...NO SIG WX EXPECTED.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...DEVOIR/LAMBERT
LONG TERM...DEVOIR/GARTNER
AVIATION...FITZGERALD/MARTIN